Hi, i have i little dent in the white area of my eye for years (probably got from my nail), how can i heal it ? i know it's harmless but it makes me worried and uncomfortable because of my dry eyes problem. thank you?

I'm not sure what exactly you mean by a "dent" but its unlikely you caused it with your nail. The white part of the eye (sclera) is the rigid outer coat. It is unlikely that anything should or could be done about an irregularity of the sclera unless it's affecting the tear film distribution contributing to your dry eyes. Most likely you are seeing an irregularity in the overlying conjunctiva.